There is no slur over b. 81-88, written in the margin of AF. It is probably Chopin's oversight, although it is also likely that the composer was afraid that a slur could have hampered the interpretation of the notation on the added staves (by hand). Anyway, there is no doubt that the added fragment was also supposed to be included in the slur encompassing b. 80 and 89, written on the main staves.
Compare the passage in the sources »
category imprint: Graphic ambiguousness; Differences between sources
issues: Inaccurate slurs in A, Errors resulting from corrections
notation: Pitch